Novel Screening Tool Using Non-linguistic Voice Features Derived from Simple Phrases to Detect Mild Cognitive Impairment and Dementia

Appropriate intervention and care in detecting cognitive impairment early are essential to effectively prevent the progression of cognitive deterioration. Diagnostic voice analysis is a noninvasive and inexpensive screening method that could be useful for detecting cognitive deterioration at earlier stages such as mild cognitive impairment. We aimed to distinguish between patients with dementia or mild cognitive impairment and healthy controls by using purely acoustic features (i.e., nonlinguistic features) extracted from two simple phrases. Voice was analyzed on 195 recordings from 150 patients (age, 45-95 years). We applied a machine learning algorithm (LightGBM; Microsoft, Redmond, WA, USA) to test whether the healthy control, mild cognitive impairment, and dementia groups could be accurately classified, based on acoustic features. Our algorithm performed well: area under the curve was 0.81 and accuracy, 66.7% for the 3-class classification. Thus, our vocal biomarker is useful for automated assistance in diagnosing early cognitive deterioration.

Hepcidin expression in the trigeminal ganglion and the oral mucosa in an oral ulcerative mucositis rat model

Severe intraoral pain induces difficulty in eating and speaking, leading to a decline in the quality of life. However, the molecular mechanisms underlying intraoral pain remain unclear. Here, we investigated gene modulation in the trigeminal ganglion and intraoral pain-related behavior in a rat model of acetic acid-induced oral ulcerative mucositis. Oral ulceration was observed on day 2 after acetic acid treatment to the oral mucosa of male Wistar rats, causing spontaneous pain and mechanical allodynia. Deoxyribonucleic acid microarray analysis of trigeminal ganglion tissue indicated that Hamp (a hepcidin gene that regulates cellular iron transport) was the most upregulated gene. In the oral ulcerative mucositis model, the upregulation of Hamp was also induced in the ulcer region but not in the liver, with no increase in hepcidin levels in the plasma and saliva, indicating that hepcidin was produced locally in the ulcer region in the model. Systemic antibiotic pretreatment did not increase the mRNA levels of Hamp in the trigeminal ganglion and ulcer regions. Hepcidin injection into the oral mucosa enhanced neuronal excitability in response to noxious mechanical stimulation of the oral mucosa in trigeminal spinal subnucleus interpolaris/caudalis neurons. These results imply that oral ulcerative mucositis induces oral mucosal pain because of infectious inflammation of the ulcerative area and potentiates Hamp, which represents anti-bacterial and anti-peptidase gene expression in the ulcer region and trigeminal ganglion. The regulation of cellular iron transport by hepcidin is likely involved in oral ulcerative mucositis-induced pain.

Ninjin'yoeito, a traditional Japanese medicine, attenuates age-related deficits of muscle performance, self-care motivation, and body temperature in C57BL/6 mice

As both physiological and psychological factors influence age-associated declines in older people, the development of drug therapy with multifaceted effects is required. To investigate the utility of ninjin'yoeito (NYT) against geriatric syndromes, we evaluated the effects of NYT on age-related declines in old C57BL/6 mice (88-week-old) as a preclinical model of frailty progression. Here, we showed that NYT reversed the decline of rectal temperature in old mice and also improved forelimb grip strength compared with that in the old control group without affecting skeletal muscle loss. Moreover, NYT significantly increased the duration of grooming after a sucrose solution was sprayed, which reflected self-care motivation. Finally, we revealed the antioxidant effects of NYT using a cell-free assay. These results suggest that NYT can improve both physiological and psychological declines associated with aging, and the mechanism may include antioxidant effects. NYT may have potential utility for maintaining the health of older people.

Ninjin'yoeito, a traditional Japanese medicine, increases dopamine content in PC12 cells

Dementia is exacerbated by loss of appetite and amotivation, and recent studies have indicated that ninjin'yoeito improves anorexia and amotivation. Previous studies suggest that ninjin'yoeito inhibits dopamine-metabolizing enzymes and enhances dopamine signaling. However, whether ninjin'yoeito increases dopamine content in living cells remains unclear. Here, PC12 cells were used to examine whether ninjin'yoeito affects the dopamine metabolic pathway. Dopamine content significantly increased 3 h after treatment ninjin'yoeito extract. Concomitantly, the levels of 3-methoxytyramine and 3,4-dihydroxyphenylacetic acid were significantly reduced. The effects of components of ninjin'yoeito on the dopamine metabolic pathway were also assessed. Treatment with onjisaponin B, nobiletin, and schisandrin, and the ingredients of Polygalae Radix, Citri Unshiu Pericarpium, and Schisandrae Fructus increased dopamine content and decreased its metabolite content in the culture media. Our findings suggest that ninjin'yoeito improves anorexia and amotivation by inhibiting metabolic enzyme and increasing the dopamine content in cells.

Ninjin'yoeito, a traditional Japanese Kampo medicine, suppresses the onset of anhedonia induced by dysfunction in the striatal dopamine receptor type 2-expressing medium spiny neurons

OBJECTIVE

Recent studies have suggested that ninjin'yoeito (NYT), a traditional Japanese Kampo medicine, improves diminished motivation in humans and animals, rendering it a novel therapeutic option for impaired motivation. To better characterize the effect of NYT on motivation, we examined its effect on motivated behaviors in mice.

METHODS

Mouse models of neurodegeneration-related apathy, in which striatal dopamine receptor type 2-expressing medium spiny neurons (D2-MSNs) were progressively damaged by diphtheria toxin expression, were chosen.

RESULTS

The decrease in effort-based operant responding for rewards (sucrose pellets), indicative of the mouse's motivated behavior, in the affected mice was not suppressed by chronic treatment with NYT suspended in drinking water at 1% (w/v). Mice were then subjected to a sucrose preference test, wherein they freely chose to ingest tap water and a sucrose solution without being required to exert effort. The affected mice showed a decline in preference for sucrose over tap water, relative to nonaffected controls, indicating anhedonia-like traits. In contrast to the diminished operant behavior, the anhedonic behavior in the affected mice was prevented by the NYT administration. Furthermore, NYT did not affect the size of Drd2 mRNA disappearance in the striatum of affected mice, suggesting that the NYT effect was unrelated to DTA-mediated neurodegeneration.

CONCLUSION

These results demonstrate that the beneficial effect of NYT on motivation is mediated, at least in part, through the potentiation of hedonic capacity by certain neuromodulatory pathways.

Evaluation of Effect of Ninjin'yoeito on Regional Brain Glucose Metabolism by 18F-FDG Autoradiography With Insulin Loading in Aged Mice

Introduction: A recent clinical study revealed that Ninjin'yoeito (NYT) may potentially improve cognitive outcome. However, the mechanism by which NYT exerts its effect on elderly patients remains unclear. The aim of this study is to evaluate the effect of Ninjin'yoeito on regional brain glucose metabolism by ¹⁸F-FDG autoradiography with insulin loading in aged wild-type mice.

Materials and Methods: After 12 weeks of feeding NYT, mice were assigned to the control and insulin-loaded groups and received an intraperitoneal injection of human insulin (2 U/kg body weight) 30 min prior to ¹⁸F-FDG injection. Ninety minutes after the injection, brain autoradiography was performed.

Results: After insulin loading, the ¹⁸F-FDG accumulation showed negative changes in the cortex, striatum, thalamus, and hippocampus in the control group, whereas positive changes were observed in the NYT-treated group.

Conclusions: Ninjin'yoeito may potentially reduce insulin resistance in the brain regions in aged mice, thereby preventing age-related brain diseases.

Evaluation of organ glucose metabolism by 18F-FDG accumulation with insulin loading in aged mice compared with young normal mice

It is important to determine the functional changes of organs that occur as a result of aging, the understanding of which may lead to the maintenance of a healthy life. Glucose metabolism in healthy bodies is one of the potential markers used to evaluate the changes of organ function. Thus, information about normal organ glucose metabolism may help to understand the functional changes of organs. [¹⁸F]-Fluoro-2-deoxy-2-d-glucose (¹⁸F-FDG), a glucose analog, has been used to measure glucose metabolism in various fields, such as basic medical research and drug discovery. However, glucose metabolism changes in aged animals have not yet been fully clarified. The aim of this study is to evaluate changes in glucose metabolism in organs and brain regions by measuring ¹⁸F-FDG accumulation and ¹⁸F-FDG autoradiography with insulin loading in aged and young wild-type mice. In the untreated groups, the levels of ¹⁸F-FDG accumulation in the blood, plasma, muscle, lungs, spleen, pancreas, testes, stomach, small intestine, kidneys, liver, brain, and brain regions, namely, the cortex, striatum, thalamus, and hippocampus, were all significantly higher in the aged mice. The treated group showed lower ¹⁸F-FDG accumulation levels in the pancreas and kidneys, as well as in the cortex, striatum, thalamus, and hippocampus in the aged mice than the untreated groups, whereas higher ¹⁸F-FDG accumulation levels were observed in those in the young mice. These results demonstrate that insulin loading decreases effect on ¹⁸F-FDG accumulation levels in some organs of the aged mice. Therefore, aging can increase insulin resistance and lead to systemic glucose metabolism dysfunction.

Author Correction: The Japanese herbal medicine Hangeshashinto enhances oral keratinocyte migration to facilitate healing of chemotherapy-induced oral ulcerative mucositis

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Yokukansankachimpihange, a traditional Japanese (Kampo) medicine, enhances the adaptation to circadian rhythm disruption by increasing endogenous melatonin levels

The traditional Japanese (Kampo) medicines yokukansan (YKS) and yokukansankachimpihange (YKSCH) have similar formulas and the same indications. In animals or cultured cells, the neuropharmacological actions of YKS are sometimes more beneficial than those of YKSCH. Since both drugs are used to treat sleep disorders in Japan, we examined the ameliorative effects of YKS and YKSCH on circadian rhythm disturbance and compared their efficacy using a mouse model of circadian rhythm disruption. Ramelteon was used as the positive control. Ramelteon treatment significantly reversed decreased running wheel activity during the advanced dark phase, indicating facilitation of circadian adaptation. YKS treatment also reversed the activity in the early period of drug treatment; however, it was not statistically significant. YKSCH treatment significantly reversed the decreased activity during the advanced dark phase. Plasma melatonin (MT) levels were significantly increased in the YKSCH but not in the YKS group. The ameliorative effect of YKSCH on rhythm disruption was significantly inhibited by coadministration of the MT₂ receptor antagonist. Therefore, the therapeutic effect of YKSCH on circadian rhythm disruption would be attributable, to elevated endogenous MT levels. Taken together, YKS and YKSCH have different pharmacological properties and may be more precisely prescribed depending on patients' psychological symptoms.

Kamikihito Enhances Cognitive Functions and Reward-Related Behaviors of Aged C57BL/6J Mice in an Automated Behavioral Assay System

The cognitive and psychological domains of frailty in the elderly have drawn increasing attention given the aging of society. However, therapeutics to treat minor deficits in cognition and mental state in the elderly remain an unmet need. Kamikihito (KKT), a traditional Japanese Kampo medicine indicated for neuroses, anxiety, and insomnia, is effective for treating cognitive dysfunction and depressive-like behaviors in animal models, suggesting that it may have therapeutic potential for treating cognitive and/or mental frailty. In this study, we first validated the known anxiolytic effects of KKT in a conventional maze test. We then introduced an automated behavioral assay system, IntelliCage, to evaluate the therapeutic potential of KKT for age-related and diverse central functions by performing sequential behavioral tasks in young and aged mice to assess basal activities, cognitive functions, perseveration, and hedonic-related behaviors. Although young mice treated with KKT did not exhibit changes in diurnal variation, KKT-administered aged mice exhibited an accelerated decline in voluntary activity during the early part of the light period, implying that KKT may promote sleep onset in aged mice. Neither place learning acquisition for gaining rewards nor subsequent behavioral flexibility performance was altered by KKT in the young group, whereas the aged KKT group exhibited significantly enhanced performance in both phases of learning relative to age-matched controls. Conversely, perseverative nose-pokes (NPs) to gain rewards observed during place learning, indicative of compulsivity, were attenuated by KKT in both age groups. Regarding hedonic processing, aged mice exhibited a decreased preference for sweet solutions compared to young mice, which was effectively reversed by KKT treatment. Furthermore, KKT elevated high-effort choices for high-value reward in an effort-based decision-making paradigm in both age groups, implying augmentation of motivational behaviors by KKT. Collectively, KKT exerted various beneficial effects in cognitive and emotional domains, several of which were more evident in aged mice than in young mice, suggesting the potential of KKT for treating cognitive and mental frailty.

The Japanese herbal medicine Hangeshashinto enhances oral keratinocyte migration to facilitate healing of chemotherapy-induced oral ulcerative mucositis

Chemotherapy often induces oral ulcerative mucositis (OUM) in patients with cancer, characterized by severe painful inflammation. Mouth-washing with the Japanese herbal medicine hangeshashinto (HST) ameliorates chemotherapy-induced OUM in patients with colorectal cancer. Previously, we demonstrated that HST decreased interleukin 1β-induced prostaglandin E2 production in human oral keratinocytes (HOKs) and OUM-induced mechanical or spontaneous pain in rats. However, HST effects on tissue repair functions in HOKs remain unclear. Here, we examined the effects of HST on scratch-induced wound healing in vitro and in vivo. In vitro, HST enhanced wound healing mainly through scratch-induced HOK migration. Screening of the seven constituent medicinal herbs and their major components revealed that Scutellaria root, processed ginger, and Glycyrrhiza components mainly induced the scratch-induced HOK migration. Pharmacokinetic analyses indicated that the active ingredient concentrations in rat plasma following oral HST administration were below the effective doses for HOK migration, suggesting direct effects of HST in OUM. Mitogen-activated protein kinase and C-X-C chemokine receptor 4 inhibitors significantly suppressed HST-induced HOK migration. Moreover, HST enhanced tissue repair in our OUM rat model. Thus, HST likely enhanced OUM tissue repair through oral keratinocyte migration upon MAPK and CXCR4 activation and may be useful in patients with cancer-associated OUM.

Influence of aging on the behavioral phenotypes of C57BL/6J mice after social defeat

Depression and anxiety are common psychiatric disorders that can occur throughout an individual’s lifetime. Numerous pathways underlying the onset of these diseases have been identified in rodents using a social defeat stress protocol, whereby socially defeated individuals exhibit depression- and/or anxiety-like phenotypes that typically manifest as social avoidance behavior. However, most studies in this field have been conducted using young adult mice; therefore, information about social defeat stress-related behavioral phenotypes in older mice is limited. In this study, we exposed groups of young adult (8–16 weeks old) and aged (24 months old) C57BL/6J mice to mild social defeat stress by challenging them with aggressive CD1 mice while restricting the intensity of aggression to protect the animals from severe injuries. We then identified stress-induced behavioral changes and compared their expression between the age groups and with a non-defeated (non-stressed) control group. We found that the stressed mice in both age groups exhibited similar reduced social interactions that were indicative of increased social avoidance behavior. Moreover, unlike the young stressed and control groups, only the aged stressed group showed a reduced preference for sucrose, which was correlated with social avoidance behavior. Also, the aged stressed mice exhibited an attenuated defeat-induced increase in water intake. These findings reveal that aging alters behavioral phenotypes after social defeat and that the hedonic behavior of aged mice is more vulnerable to social defeat compared with younger mice.

Endothelin-1 Elicits TRP-Mediated Pain in an Acid-Induced Oral Ulcer Model

Oral ulcer is the most common oral disease and leads to pain during meals and speaking, reducing the quality of life of patients. Recent evidence using animal models suggests that oral ulcers induce cyclooxygenase-dependent spontaneous pain and cyclooxygenase-independent mechanical allodynia. Endothelin-1 is upregulated in oral mucosal inflammation, although it has not been shown to induce pain in oral ulcers. In the present study, we investigated the involvement of endothelin-1 signaling with oral ulcer-induced pain using our proprietary assay system in conscious rats. Endothelin-1 was significantly upregulated in oral ulcers experimentally induced by topical acetic acid treatment, while endothelin-1 production was suppressed by antibacterial pretreatment. Spontaneous nociceptive behavior in oral ulcer model rats was inhibited by swab applications of BQ-788 (ET_B receptor antagonist), ONO-8711 (prostanoid receptor EP₁ antagonist), and HC-030031 (TRPA1 antagonist). Prostaglandin E₂ production in the ulcers was suppressed by BQ-788. Mechanical allodynia in the model was inhibited not only by BQ-788 and HC-030031 but also by BQ-123 (ET_A receptor antagonist), SB-366791 (TRPV1 antagonist), and RN-1734 (TRPV4 antagonist). In naive rats, submucosal injection of endothelin-1 caused mechanical allodynia that was sensitive to HC-030031 and SB-366791 but not to RN-1734. These results suggest that endothelin-1 production following oral bacterial invasion via ulcerative regions elicits TRPA1-mediated spontaneous pain. This pain likely occurs through an indirect route that involves ET_B receptor-accelerated prostanoid production. Endothelin-1 elicits directly TRPA1- and TRPV1-mediated mechanical allodynia via both ET_A and ET_B receptors on nociceptive fibers. The TRPV4-mediated allodynia component seems to be independent of endothelin signaling. These findings highlight the potential of endothelin signaling blockers as effective analgesic approaches for oral ulcer patients.

An effective therapeutic approach for oxaliplatin-induced peripheral neuropathy using a combination therapy with goshajinkigan and bushi

Oxaliplatin-induced peripheral neuropathy (OIPN) occurs at extraordinarily high frequency, but no effective treatment for this disorder has been established. Goshajinkigan (GJG), a traditional Japanese medicine known as Kampo, is known to reduce OIPN in both basic and clinical studies. However, its molecular mechanisms remain largely unknown. Here, we elucidate the mechanisms underlying the therapeutic effects of GJG against OIPN and the therapeutic benefits of combining GJG with bushi, a herbal medicine derived from the processed Aconiti tuber. Oxaliplatin (4 mg/kg) was injected into mice twice a week for up to 4 and 3 weeks, respectively. OIPN was assessed using pain behavioral tests, such as those testing cold hypersensitivity, thermal hyperalgesia, and mechanical allodynia, as well as a reduction of the current perception threshold (CPT). GJG (0.3 or 1 g/kg) and bushi (0.1 or 0.3 g/kg) were orally administered 5 times a week for 4 weeks. Behavioral analysis was performed 24 h after the final dose.

Oxaliplatin induced cold hypersensitivity and mechanical allodynia but not thermal hyperalgesia and reduced CPT of Aδ- and Aβ-fibers but not C-fibers. All these effects were counteracted by GJG. Bushi, an ingredient of GJG that shows analgesic effect, reduced oxaliplatin-induced cold hypersensitivity but had no effect on oxaliplatin-induced mechanical allodynia. However, bushi significantly accentuated the effects of GJG when co-administered with GJG. GJG reduces OIPN by counteracting the sensitization of Aδ- and Aβ-fibers and shows analgesic effects against cold hypersensitivity and mechanical allodynia. These effects are potentiated by bushi. The combination of GJG with bushi has high potential for preventing OIPN.

Difference in voice analysis result by pre- and post- processing of telephone line

The purpose of this study is to verify the impact of a deterioration of the sound quality of voice by a telephone line on estimating Vitality as the extent of depressive tendency based on voice analysis using MIMOSYS. First, the voices of about 1,000 people recorded using a recorder were prepared. Next, each voice was coded and resampled in preparation for transmission over a phone line. Vitalities obtained by analyzing the voices before and after these processes were compared. The results showed high correlation between the Vitality after coding and Vitality before coding, revealing that using a telephone would be an effective way to obtain voices.

[6]-gingerol and [6]-shogaol, active ingredients of the traditional Japanese medicine hangeshashinto, relief oral ulcerative mucositis-induced pain via action on Na+ channels

The traditional Japanese herbal medicine hangeshashinto (HST) has beneficial effects for the treatment of oral ulcerative mucositis (OUM) in cancer patients. However, the ingredient-based mechanism that underlies its pain-relieving activity remains unknown. In the present study, to clarify the analgesic mechanism of HST on OUM-induced pain, we investigated putative HST ingredients showing antagonistic effects on Na⁺ channels in vitro and in vivo. A screen of 21 major ingredients using automated patch-clamp recordings in channel-expressing cells showed that [6]-gingerol and [6]-shogaol, two components of a Processed Ginger extract, considerably inhibited voltage-activated Na⁺ currents. These two ingredients inhibited the stimulant-induced release of substance P and action potential generation in cultured rat sensory neurons. A submucosal injection of a mixture of [6]-gingerol and [6]-shogaol increased the mechanical withdrawal threshold in healthy rats. In a rat OUM model, OUM-induced mechanical pain was alleviated 30min after the swab application of HST despite the absence of anti-bacterial and anti-inflammatory actions in the OUM area. A swab application of a mixture of [6]-gingerol and [6]-shogaol induced sufficient analgesia of OUM-induced mechanical or spontaneous pain when co-applied with a Ginseng extract containing abundant saponin. The Ginseng extract demonstrated an acceleration of substance permeability into the oral ulcer tissue without an analgesic effect. These findings suggest that Na⁺ channel blockage by gingerol/shogaol plays an essential role in HST-associated analgesia of OUM-induced pain. This pharmacological mechanism provides scientific evidence supporting the use of this herbal medicine in patients suffering from OUM-induced pain.

Ignavine: a novel allosteric modulator of the μ opioid receptor

Processed Aconiti tuber (PAT) is used to treat pain associated with various disorders. Although it has been demonstrated that the κ opioid receptor (KOR) signaling pathway is a mediator of the analgesic effect of PAT, active components affecting opioid signaling have not yet been identified. In this study, we explored candidate components of PAT by pharmacokinetic analysis and identified ignavine, which is a different structure from aconitine alkaloids. A receptor binding assay of opioid receptors showed that ignavine specifically binds the μ opioid receptor (MOR), not the KOR. Receptor internalization assay in MOR-expressing cell lines revealed that ignavine augmented the responses produced by D-Ala(2)-N-Me-Phe(4)-Gly-ol(5)-enkephalin (DAMGO), a representative MOR agonist, at a low concentration and inhibited it at a higher concentration. Ignavine also exerted positive modulatory activity for DAMGO, endomorphin-1 and morphine in cAMP assay. Additionally, ignavine alone showed an analgesic effect in vivo. In silico simulation analysis suggested that ignavine would induce a unique structural change distinguished from those induced by a representative MOR agonist and antagonist. These data collectively suggest the possibility that ignavine could be a novel allosteric modulator of the MOR. The present results may open the way for the development of a novel pain management strategy.

The traditional Japanese medicine hangeshashinto alleviates oral ulcer-induced pain in a rat model

OBJECTIVE

Recent studies have demonstrated that mouthwash made with the traditional Japanese medicine hangeshashinto exhibits anti-inflammatory action and alleviates oral mucositis scores, including pain complaints, in patients undergoing chemoradiotherapy. However, no study has demonstrated the mechanism underlying how hangeshashinto provides pain relief in oral ulcers.

DESIGN

The analgesic effects on pain-related behaviors following the topical application of hangeshashinto were evaluated in an oral ulcer rat model treated with acetic acid using recently developed methods. Indomethacin, the representative anti-inflammatory agent, was intraperitoneally administered. The tissue permeability of the oral mucosa was histologically evaluated after applying the fluorescent substance FluoroGold.

RESULTS

The topical application of hangeshashinto in ulcerative oral mucosa suppressed mechanical pain hypersensitivity over 60 min, without any effects on healthy mucosa. The same drug application also inhibited oral ulcer-induced spontaneous pain. Indomethacin administration failed to block the mechanical pain hypersensitivity, though it did largely block spontaneous pain. Topical anesthesia with lidocaine showed hyposensitivity to mechanical stimulation in healthy mucosa. In the ulcer regions in which the oral epithelial barrier was destroyed, deep parenchyma was stained with FluoroGold, in contrast to healthy oral mucosa, in which staining was limiting to the superficial site.

CONCLUSIONS

Hangeshashinto leads to long-lasting analgesic effects, specifically in the ulcer region by destroying the epithelial barrier. Hangeshashinto alleviates oral ulcer-induced pain in inflammation-dependent and/or independent manner.

Preventive effect of oral goshajinkigan on chronic oxaliplatin-induced hypoesthesia in rats

Oxaliplatin, a widely used chemotherapeutic agent, induces peripheral neuropathy that manifests itself as two distinct phases: acute cold hyperesthesia and chronic peripheral hypoesthesia/dysesthesia. The latter is a serious dose-limiting side effect that can often lead to withdrawal of treatment. We have developed a rat model expressing both phases and used the model to investigate the action of goshajinkigan (GJG), a traditional Japanese herbal medicine, which was reported to ameliorate oxaliplatin-induced neuropathy in a placebo-controlled double-blind randomized phase II study. In this study, neuropathy was induced by injection of oxaliplatin twice weekly for 8 wks. The maximum level of cold hyperesthesia was observed at 4 wks with heat hypoesthesia developing later. Microscopy studies revealed atrophy of axons of myelinated sciatic nerve fibers in oxaliplatin-treated rats at 8 wks. Co-administration of GJG ameliorated both abnormal sensations as well as histological damage to the sciatic nerve. A pharmacokinetic study revealed numerous neuroprotective components of GJG that are rapidly absorbed into the blood. GJG and some of its components attenuated the generation of oxaliplatin-induced reactive oxygen species, which is a possible mechanism of oxaliplatin-induced neurotoxicity. The present study provides a useful animal model for oxaliplatin-induced neurotoxicity as well as a promising prophylactic agent.

Analysis of the antioxidative function of the radioprotective Japanese traditional (Kampo) medicine, hangeshashinto, in an aqueous phase

Oral mucositis (OM) is a common and painful complication of radiotherapy for head and neck cancer. Hangeshashinto (HST), a Japanese traditional medicine, is known to alleviate radiotherapy- and/or chemotherapy-induced OM; however, the detailed mechanism has not yet been clarified. The aim of the present study was to clarify the details of the antioxidative functions of HST against reactive oxygen species (ROS) produced by radiation. The hydroxyl radical (•OH)-scavenging ability and the reduction ability was simultaneously measured using a modified electron paramagnetic resonance (EPR) spin-trapping method. The superoxide (O(2) (•-))-scavenging ability was estimated by an EPR redox probing method. Water suspensions of powdered HST and of its seven constitutive crude drugs were tested. In addition, some of the main water-soluble ingredients of the crude drugs were also tested. HST was found to scavenge both •OH and O(2) (•-). Furthermore, HST was observed to reduce relatively stable nitroxyl radicals. Glycyrrhizae Radix (kanzo), Ginseng Radix (ninjin), Zizyphi Fructus (taiso) and glycyrrhizin (an ingredient of kanzo) were all found to be relatively good •OH scavengers. Scutellariae Radix (ogon) and Coptidis Rhizoma (oren) demonstrated reducing ability. In addition, acteoside and berberine chloride, which are water-soluble ingredients of ogon and oren, respectively, also demonstrated reducing ability. Oren exhibited oxidative ability at higher concentrations, which may have a function in maintaining catalytic redox action. The antioxidative function of HST probably worked via a balance of scavenging ROS, reducing stable free radicals, and some minor oxidizing activities.

Effects of shakuyakukanzoto and its absorbed components on twitch contractions induced by physiological Ca2+ release in rat skeletal muscle

Shakuyakukanzoto (SKT) is a kampo medicine composed of equal proportions of Glycyrrhizae radix (G. radix) and Paeoniae radix (P. radix). A double-blind study reported that SKT significantly ameliorated painful muscle cramp in cirrhosis patients without the typical severe side effects of muscle weakness and central nervous system (CNS) depression. Previous basic studies reported that SKT and its active components induced relaxation by a direct action on skeletal muscle and that SKT did not depress CNS functions; however, why SKT has a lower incidence of muscle weakness remains unknown. In the present study, we investigated which components are absorbed into the blood of rats after a single oral administration of SKT to identify the active components of SKT. We also investigated the effects of SKT and its components on the twitch contraction induced by physiological Ca²⁺ release. Our study demonstrated that SKT and five G. radix isolates, which are responsible for the antispasmodic effect of SKT, did not inhibit the twitch contraction in contrast to dantrolene sodium, a direct-acting peripheral muscle relaxant, indicating that the mechanisms of muscle contraction of SKT and dantrolene in skeletal muscle differ. These findings suggest that SKT does not reduce the contractile force in skeletal muscle under physiological conditions, i.e., SKT may have a low risk of causing muscle weakness in clinical use. Considering that most muscle relaxants and anticonvulsants cause various harmful side effects such as weakness and CNS depression, SKT appears to have a benign safety profile.

Efficacy of Goshajinkigan for prophylaxis against oxaliplatin-induced peripheral neuropathy

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Background: Oxaliplatin-induced peripheral neuropathy (OPN) is often observed and is the most frequent dose-limiting toxicity. However, there is no effective therapeutic option for preventing OPN. Goshajinkigan (GJG), a traditional Japanese herbal medicine, has widely been used for disease-assessed neuropathy in Japan. Recently, the preventive effect of GJG against OPN in a placebo-controlled double-blind randomized phase II study was reported (Kono T et al., Cancer Chemother Pharmacol. 2013, 72,1283-90). However, the precise mechanisms underlying preventive effect of GJG are unknown. Methods: To be established the OPN rat model, oxaliplatin (4 mg/kg) was injected intraperitoneally twice weekly for 8 weeks in rats. Animals were treated with oral administration of GJG (0.3, 1.0 g/kg) five times a week for 8 weeks. We performed behavioral tests (acetone test and hot plate test) and pathological examination of neuronal tissue using the OPN rat model. We carried out pharmacokinetic study of GJG and searched for active ingredients in GJG in order to explore the mechanism of GJG. Results: The rats injected with oxaliplatin for a long-term showed both cold hypersensitivity and heat hyposensitivity. Co-administration of GJG ameliorated OPN in the rat. In light and electron microscopic study, scattered axonal damages in sciatic nerve of oxaliplatin groups were observed, which were substantially suppressed by GJG. Pharmacokinetic study revealed that considerable neuroprotective and analgesic ingredients were detected after oral administration of GJG in rat plasma. Some ingredients in GJG significantly suppressed oxidative stress caused by oxaliplatin in the experiment using neuronal cells. Conclusions: Oxaliplatin-induced chronic neuropathy symptoms are similar to human symptoms caused by long-term oxaliplatin administration. Oral administration of GJG in rat substantially diminished OPN, and promises to provide an effective and convenient treatment at risk of developing peripheral neuropathy in oxaliplatin-treated patients.

Goshajinkigan, a traditional Japanese medicine, prevents oxaliplatin-induced acute peripheral neuropathy by suppressing functional alteration of TRP channels in rat

The acute peripheral neuropathy induced by oxaliplatin treatment occurs very frequently and is aggravated by exposure to cold. Goshajinkigan (GJG), a traditional Japanese (kampo) medicine, was recently shown to be effective against oxaliplatin-induced acute neuropathy. However, because the effects of GJG and its mechanism in relation to those of its ingredients and its mechanism are not well understood, we examined the effects of GJG on acute neuropathy. Further, we investigated whether GJG affects the functions and gene expressions of transient receptor potential (TRP) channels using a rat model of oxaliplatin-induced neuropathy. Administration of oxaliplatin increased withdrawal responses from cold stimulation, and GJG or calcium gluconate/magnesium sulfate significantly inhibited the oxaliplatin-induced cold hypersensitivity. Application of menthol, a TRPA1/TRPM8 agonist, or allyl isothiocyanate (AITC), a selective TRPA1 agonist, to the hind paw of oxaliplatin-treated rats enhanced the nocifensive behaviors evoked by each agonist, whereas oxaliplatin had no significant effect on nocifensive behaviors evoked by capsaicin, a TRPV1 agonist. GJG treatment reduced menthol- or AITC-evoked withdrawal responses potentiated by oxaliplatin. Furthermore, GJG suppressed the increase of TRPA1 and TRPM8 mRNA expression induced by oxaliplatin in dorsal root ganglia. These findings suggest that GJG prevented oxaliplatin-induced acute peripheral neuropathy by suppressing functional alteration of TRP channels, especially TRPA1 and TRPM8.

Traditional Japanese oral mucositis medicine hangeshashinto to upregulate antimicrobial peptides in human salivary gland cells

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Background: The cause of chemotherapy-induced oral mucositis (COM) is thought to be direct injury and indirect stomatotoxic effects that result from the release of inflammatory mediators, loss of protective salivary constituents, and therapy-induced neutropenia. We previously found that gargling with hangeshashinto (HST), a traditional Japanese medicine, was effective for treatment of COM. Focusing on the pain and inflammation of COM, we reported at ASCO-GI 2013 and DDW 2013 that HST exhibited ameliorating effects in a hamster model of COM and multi-targeted effects on prostaglandin E2 (PGE2) production, followed by identification of active ingredients by PGE2 culture systems and LC-MS/MS. Our aim in this study was to address whether HST affects protective oral constituents. Methods: Human oral keratinocytes (HOK) and human salivary gland (HSG) cells were used for cell culture assays. Expression levels of mRNAs for antimicrobial peptides, extracellular matrixes, keratinocyte growth factor, amylase, COX-1/COX-2, and cNOS/iNOS in cells with or without HST (10–300 μg/mL) treatment were measured by RT-PCR. Results: HST increased gene expressions of some antimicrobial peptides (defensin β1, adrenomedullin, cathelicidin antimicrobial peptide), and amylase 1A in HSG cells. Further, HST dramatically inhibited COX-2 and iNOS mRNAs in IL-1β treated HOK cells, while it exerted no or little effect on expressions of any protective oral constituents in non-treated HOK cells. A random test to identify the ingredients that increase defensin β1 revealed that isoquinoline alkaloids like berberine were active. Conclusions: HST is expected to maintain oral homeostasis through two paths: increased production of antimicrobial peptides and decreased oral damage induced by excessive prostanoids and nitric oxide. HST thus functions as a multitarget agent, indicating that it may be beneficial in COM treatment.

Epithelial transient receptor potential ankyrin 1 (TRPA1)-dependent adrenomedullin upregulates blood flow in rat small intestine

The functional roles of transient receptor potential (TRP) channels in the gastrointestinal tract have garnered considerable attention in recent years. We previously reported that daikenchuto (TU-100), a traditional Japanese herbal medicine, increased intestinal blood flow (IBF) via adrenomedullin (ADM) release from intestinal epithelial (IE) cells (Kono T et al. J Crohns Colitis 4: 161-170, 2010). TU-100 contains multiple TRP activators. In the present study, therefore, we examined the involvement of TRP channels in the ADM-mediated vasodilatatory effect of TU-100. Rats were treated intraduodenally with the TRP vanilloid type 1 (TRPV1) agonist capsaicin (CAP), the TRP ankyrin 1 (TRPA1) agonist allyl-isothiocyanate (AITC), or TU-100, and jejunum IBF was evaluated using laser-Doppler blood flowmetry. All three compounds resulted in vasodilatation, and the vasodilatory effect of TU-100 was abolished by a TRPA1 antagonist but not by a TRPV1 antagonist. Vasodilatation induced by AITC and TU-100 was abrogated by anti-ADM antibody treatment. RT-PCR and flow cytometry revealed that an IEC-6 cell line originated from the small intestine and purified IE cells expressed ADM and TRPA1 but not TRPV1. AITC increased ADM release in IEC cells remarkably, while CAP had no effect. TU-100 and its ingredient 6-shogaol (6SG) increased ADM release dose-dependently, and the effects were abrogated by a TRPA1 antagonist. 6SG showed similar TRPA1-dependent vasodilatation in vivo. These results indicate that TRPA1 in IE cells may play an important role in controlling bowel microcirculation via ADM release. Epithelial TRPA1 appears to be a promising target for the development of novel strategies for the treatment of various gastrointestinal disorders.

Antispasmodic effect of shakuyakukanzoto extract on experimental muscle cramps in vivo: role of the active constituents of Glycyrrhizae radix

ETHNOPHARMACOLOGICAL RELEVANCE

Shakuyakukanzoto (SKT) composed of Glycyrrhizae radix (G. radix) and Paeoniae radix (P. radix) has been traditionally used in Japan, Korea and China as an antispasmodic drug for the treatment of skeletal muscle cramps and intestinal cramps.

AIM OF THIS STUDY

To evaluate the antispasmodic activity of SKT and its two components, as well as to identify the key constituents of the components which mediate this effect in skeletal muscles in vivo.

MATERIALS AND METHODS

An experimental cramp model was constructed to evaluate the effects of peripherally-acting muscle relaxants on electrically-induced cramps under physiological conditions. This was accomplished by surgically isolating the motor supply to the gastrocnemius muscle in an anesthetized rat and delivering electrical stimuli to an isolated tibial nerve to induce tetanic contractions. We first tested dantrolene, a well-known peripherally-acting relaxant, to determine the sensitivity and reliability of our experimental model. We then evaluated the effects of SKT, P. radix, G. radix, and the eight active constituents of G. radix against tetanic contractions.

RESULTS

We found that dantrolene (10 and 30 mg/kg, i.d.) rapidly and significantly inhibited tetanic contractions (P<0.01) irrespective of dose. SKT (0.5, 1.0, and 2.0 g/kg, i.d.) and G. radix (0.5 and 1.0 g/kg, i.d.) also significantly inhibited tetanic contractions (P<0.01) but in a dose-dependent manner owing to the actions of six of the eight active constituents in G. radix (liquiritin apioside, liquiritigenin, isoliquiritin apioside, isoliquiritigenin, glycycoumarin, and glycyrrhetinic acid, 20 μmol/kg, i.v.). These constituents, which include flavonoids, a triterpenoid, and a courmarin derivative, demonstrated temporal variations in their inhibitory activity. In contrast, P. radix (0.5 and 1.0 g/kg, i.d.) did not show a statistically significant antispasmodic effect in our study; however, we previously found that it had a significant antinociceptive effect.

CONCLUSIONS

Our findings show that SKT inhibits tetanic contractions in vivo and that G. radix is the main antispasmodic component due to the actions of its active constituents, thus supporting the traditional use of SKT. We further propose that SKT containing the antispasmodic G. radix and antinociceptive P. radix is a pharmaceutically elegant option for muscle cramps as treatment requires a two-pronged approach, i.e., inhibition of hyperexcitable skeletal tissues and modulation of the pain accompanying cramps.

Daikenchuto (TU-100) ameliorates colon microvascular dysfunction via endogenous adrenomedullin in Crohn's disease rat model

BACKGROUND

Daikenchuto (TU-100), a traditional Japanese medicine, has been reported to up-regulate the adrenomedullin (ADM)/calcitonin gene-related peptide (CGRP) system, which is involved in intestinal vasodilatation. The microvascular dysfunction of the intestine in Crohn's disease (CD), due to down-regulation of the ADM/CGRP system, is etiologically related to the recurrence of CD. Therefore, we investigated the vasodilatory effect of TU-100 in a CD rat model.

METHODS

Colitis was induced by the rectal instillation of 2,4,6-trinitrobenzenesulfonic acid (TNBS) in rats. Laser Doppler blood flowmetry was used to measure colonic blood flow. ADM, CGRP, and their receptors in the ischemic colon were measured by reverse transcription polymerase chain reaction (RT-PCR) and enzyme immunoassays. Additionally, we determined whether the intestinal epithelial cell line IEC-6 released ADM in response to TU-100.

RESULTS

TU-100 increased blood flow in ischemic segments of the colon but not in hyperemic segments. Pretreatment with an antibody to ADM abolished the vasodilatory effect of TU-100. CGRP levels and βCGRP mRNA expression were decreased in the ischemic colon, while protein and mRNA levels of ADM were unchanged. Hydroxy α-sanshool, the main constituent of TU-100, was the most active component in improving blood flow. Additionally, both TU-100 and hydroxy α-sanshool enhanced the release of ADM from IEC-6 cells.

CONCLUSIONS

In the ischemic colon, endogenous βCGRP, but not ADM, was decreased. Thus, it was concluded that TU-100 ameliorated microvascular dysfunction by the up-regulation of endogenous ADM in the CD rat model. TU-100 may be a possible therapeutic agent for gastrointestinal ischemia-related diseases including CD.

Role of alpha2-adrenoceptors in enhancement of antinociceptive effect in diabetic mice

The present studies investigated behavioral and neurochemical aspects of the noradrenergic and serotonergic nervous systems in streptozotocin-induced diabetic mice. We previously reported that intrathecal (i.t.) injection of norepinephrine significantly potentiated antinociception in diabetic mice compared to that in non-diabetic mice, and that antinociception due to norepinephrine injection was completely abolished by pretreatment with yohimbine, an alpha2-adrenoceptor antagonist. The present studies demonstrated that i.t. injection of clonidine also showed more-potent antinociceptive activity in diabetic mice than in non-diabetic mice, but that i.t. methoxamine injection did not affect diabetic or non-diabetic mice. The antinociceptive potency due to i.t. injection of 5-HT was significantly lower in diabetic than in non-diabetic mice. In a neurochemical study, we found that the density of [3H]-rauwolscine binding sites in spinal alpha2-adrenoceptors was significantly higher in diabetic than in non-diabetic mice, but that the binding affinity was unchanged. Spinal norepinephrine turnover was determined by measuring the decline in tissue norepinephrine concentration at 3 h after injection of the tyrosine hydroxylase inhibitor alpha-methyl-p-tyrosine. The spinal norepinephrine concentration decreased to 43.7% from the baseline in non-diabetic mice, while it was 21.0% in diabetic mice. These results suggest that, based on the decrease of norepinephrine release in the spinal cord, up-regulation of spinal alpha2-adrenoceptors caused the increase of antinociception due to i.t. injection of an alpha2-adrenoceptor agonist in streptozotocin-induced diabetic mice, and it seemed that the stimulation of alpha2-adrenoceptors potentiated the antinociceptive effect. Thus, the spinal noradrenergic systems play an important moderating role in diabetes-induced neuropathic pain.

Antinociceptive Effect of Shakuyakukanzoto, a Kampo Medicine, in Diabetic Mice

In this study, the antinociceptive effect of shakuyakukanzoto was investigated using streptozotocin-induced diabetic mice to certify its analgesic effect on diabetic patients. Shakuyakukanzoto (0.5 and 1.0 g/kg, p.o.) significantly increased the nociceptive threshold in diabetic mice. The antinociceptive activity of shakuyakukanzoto in diabetic mice was not antagonized by beta-funaltrexamine, naltrindole, or nor-binaltorphimine. The increased antinociceptive activity of (1.0 g/kg, p.o.) in diabetic mice was abolished by yohimbine (15 microg, i.t.), but not by NAN-190 (1 microg, i.t.), methysergide (15 microg, i.t.), or MDL-72222 (15 microg, i.t.). In shakuyakukanzoto diabetic mice treated with 6-hydroxydopamine (20 microg, i.t.) chemically lesioned noradrenergic pathways, shakuyakukanzoto (1.0 g/kg, p.o.) failed to exhibit an antinociceptive effect. Furthermore, the antinociceptive activity induced by norepinephrine (0.06 - 2 microg, i.t.) was markedly more potent in diabetic mice than in non-diabetic mice at the same dose. These results suggest that the antinociceptive effect of shakuyakukanzoto in diabetic mice is not mediated by the opioid systems and that this effect appears via selective activation of the spinal descending inhibitory alpha2-adrenergic systems without activating the serotonergic systems. The spinal alpha2-adrenoceptor-mediated analgesic mechanism was enhanced in diabetic mice, suggesting that shakuyakukanzoto exhibits its effect by activating the descending noradrenergic neurons.

8-O-cinnamoylneoline, a new alkaloid from the flower buds of Aconitum carmichaeli and its toxic and analgesic activities

From flower buds of Aconitum carmichaeli Debx., a new alkaloid, 8- O-cinnamoylneoline, was isolated. The structure of the new alkaloid was determined by spectral analysis, and the alkaloid was examined for its toxic and analgesic activities. Its LD50 value was 11.89 mg/kg (s.c.) in mice: the toxicity was 1/30 times that of mesaconitine and 20 times that of benzoylmesaconine. Its ED50 value was 0.86 mg/kg (s.c.) in mice using the tail pressure method: its analgesic effect was 1/40 times that of mesaconitine and 45 times that of benzoylmesaconine. Its safety margin (= LD50/ED50) was higher than that of benzoylmesaconine but lower than that of mesaconitine.

Reconstruction of knee ligaments with a free tensor fascia lata myocutaneous flap transfer

A 26-year-old woman suffered a grinding injury of the thigh and knee, resulting in the loss of a large amount of soft tissue and some of the femur. A contralateral tensor fascia lata myocutaneous free flap was used to reconstruct the soft tissues and the lateral ligament compartment around the knee. Later, a ceramic artificial bone was implanted. The patient was able to walk, and a stress radiograph showed that the implanted artificial bone and the knee joint were stable. There was no donor-site morbidity. The functional and cosmetic results were satisfactory.

Cranial-bone defects with depression deformity treated with ceramic implants and free-flap transfers

Hydroxyapatite ceramic has many advantages in the treatment of cranial-bone defects. However, for large skull defects with severe depression deformities, it may be risky to use ceramic implants because an extradural dead space will be left and the overlying scalp will have to be closed under tension. In these cases microvascular free-flap transfers are a good solution. We have treated three patients for large skull defects with severe depression deformities after repeated local infections and several operations or irradiation. A latissimus dorsi myocutaneous flap was combined with a serratus anterior muscle flap to fill the extradural space under the ceramic implant in the first patient. A latissimus dorsi muscle flap was inserted under the ceramic implant in an irradiated site and a combined small serratus anterior muscle flap was used as a monitor in the second patient. A latissimus dorsi myocutaneous flap was used to cover the ceramic implant and fill the scalp defect in the third patient. The follow-up periods varied from 12 to 35 months (mean: 20.7 months). The clinical courses of all three patients were uneventful and no flap was lost. The extradural space can be reduced to some extent by making the ceramic implant slightly flatter or thicker, but in patients with severe depression deformities, whose brain expansion cannot be expected, a muscle flap should be transferred into the space.

Mandibular contour reconstruction with three-dimensional computer-assisted models

Facial contours are thought to depend on the appropriate balance of hard and soft tissue. To obtain aesthetically good results in head and neck reconstruction, surgeons should know the exact three-dimensional shape and volume of both hard and soft tissue to be reconstructed. The authors used computer-assisted three-dimensional solid models of the mandible in 7 patients (4 women and 3 men) who underwent mandibular contour reconstruction. Scapular osteocutaneous flaps were used in all 7 patients. The follow-up periods ranged from 7 to 57 months (mean follow-up, 29 months). No flap was lost. One patient died of metastatic cancer. In 2 patients the aesthetic results were excellent and in 4 patients they were good. Computer-assisted three-dimensional models for mandibular contour reconstruction in head and neck reconstruction are quite useful.

Antinociceptive effect of U-50488H, a kappa-opioid agonist, in streptozotocin-induced diabetic mice

We compared the antinociceptive activity of a kappa-opioid agonist, U-50488H, in streptozotocin-induced diabetic mice with that in non-diabetic mice. Subcutaneously administered U-50488H (3 and 10 mg kg(-1)) showed a more potent antinociceptive effect, as evaluated by the tail-pressure method, in diabetic mice than in non-diabetic mice. Increased antinociceptive activity of U-50488H observed in diabetic mice was also observed in mice given U-50488H intrathecally (3 and 10 microg). However, there were no differences observed between diabetic and non-diabetic mice given U-50488H intracerebroventricularly (3 and 10 microg). Although the antinociceptive effect of U-50488H (3 mg kg(-1), s.c.) in non-diabetic mice was increased by treatment with PD135158 (100 ng, i.c.v.), a cholecystokininB (CCKB) antagonist, the antinociceptive activity of U-50488H which was enhanced in diabetic mice was not influenced by PD135158. Moreover, the increased antinociceptive activity of U-50488H (3 mg kg(-1), s.c.) in diabetic mice diminished when desulfated octapeptide of cholecystokinin (3-100 ng, i.c.v.), a CCKB agonist, was administered. These results suggested that diabetic mice were selectively hyper-responsive to spinal kappa-opioid receptor-mediated antinociception. The function of the analgesia inhibitory system in which cholecystokinin is used as a transmitter might be diminished in diabetic mice.

Changes in analgesia-producing mechanism of repeated cold stress loading in mice

Functional changes in opioid receptors involved in analgesia of repeated cold stress (RCS)-loaded mice were investigated. The antinociceptive potency of morphine (4 mg/kg, PO) was not affected in normal mice by norbinaltorphimine (10 mg/kg, SC), but treatment with this agent resulted in a lower level of morphine-induced antinociception in RCS-loaded animals. The antinociceptive activity of U-50488H (3 mg/kg, SC) was increased in RCS-loaded mice. In contrast to hypersensitivity to U-50488H (1 and 10 microg, IT) noted in RCS-loaded mice, the antinociception induced by DAMGO (0.1 and 1 microg, ICV) was reduced compared to that of normal animals. Diazepam (1 mg/kg/day SC) was given during RCS loading, and this agent prevented the development of hyperalgesia and the decrease in the antinociceptive activity of DAMGO (1 microg, ICV) in RCS-loaded mice, but there was no effect on the enhancement of the antinociceptive potency of U-50488H (10 microg, IT). These results indicate that the RCS-loaded mice were hyposensitive to supraspinal mu-opioid receptor-mediated antinociception, whereas their antinociceptive activities through kappa-opioid receptor in the spinal cord were increased. Hypofunction of the supraspinal mu-opioid receptor due to anxiety may explain the mechanism involved in the lowering of the nociceptive threshold in RCS-loaded animals.

Analgesia-producing mechanism of processed Aconiti tuber: role of dynorphin, an endogenous kappa-opioid ligand, in the rodent spinal cord

The analgesia-producing mechanism of processed Aconiti tuber was examined using rodents whose nociceptive threshold was decreased by loading repeated cold stress (RCS). The antinociceptive effect of processed Aconiti tuber (0.3 g/kg, p.o.) in RCS-loaded mice was antagonized by pretreatment with a kappa-opioid antagonist, nor-binaltorphimine (10 mg/kg, s.c.), and was abolished by an intrathecal injection of anti-dynorphin antiserum (5 microg). The Aconiti tuber-induced antinociception was inhibited by both dexamethasone (0.4 mg/kg, i.p.) and a dopamine D2 antagonist, sulpiride (10 mg/kg, i.p.), in RCS-loaded mice, and it was eliminated by both an electric lesion of the hypothalamic arcuate nucleus (HARN) and a highly selective dopamine D2 antagonist, eticlopride (0.05 microg), administered into the HARN in RCS-loaded rats. These results suggest that the analgesic effect of processed Aconiti tuber was produced via the stimulation of kappa-opioid receptors by dynorphin released in the spinal cord. It was also shown that dopamine D2 receptors in the HARN were involved in the expression of the analgesic activity of processed Aconiti tuber.

A flap to monitor a temporoparietal fascial flap. Case report

The temporoparietal fascial flap is useful in reconstructions of the hands and feet as tendon gliding material, but it is difficult to monitor its viability postoperatively. We have monitored such flaps by attaching a small preauricular skin flap 2 x 1 cm in size to the vascular pedicle. This preauricular island flap can be used as a "monitoring" flap.

Antinociceptive mechanism of the aconitine alkaloids mesaconitine and benzoylmesaconine

We explored the possible role of the specific regions in the brain stem on the antinociceptive actions of mesaconitine (MA) and benzoylmesaconine (BM) by the microinjection of MA and BM into nucleus reticularis paragigantocellularis (NRPG), nucleus raphe magnus (NRM), and periaqueductal gray (PAG). MA microinjected into NRPG, NRM, or PAG elicited a dose-dependent antinociceptive action, whereas BM injected into NRM or PAG elicited a dose-dependent antinociceptive action but not in NRPG. The NRM appeared to be the most sensitive region among the three tested locations.

The analgesic mechanism of processed Aconiti tuber: the involvement of descending inhibitory system

Tsumura-shuchi-bushi-matsu (TJ-3021) is a processed Aconiti tuber which has a potent antinociceptive action. The present study was undertaken to study the analgesic mechanism produced by TJ-3021. RCS (repeated cold stress) rats in hyperalgesia were markedly suppressed by oral administration of TJ-3021. Intrathecal and intraperitoneal administration of a selective alpha 2-adrenoreceptor antagonist, idazoxan (IDA), reduced significantly the analgesic effect of TJ-3021 in RCS rats. Methysergide (METH), a 5-HT receptor antagonist, demonstrated a similar effect, while intraperitoneal administration of opioid receptor antagonist, naloxone, did not produce the effect. Both oral and intracisternal administration of mesaconitine (MA) which is one of the main potent alkaloids contained in TJ-3021 produced analgesic effect in non-RCS rats.